FORAMEN MAGNUM – A STUDY ON ITS MORPHOMETRY AMONG THE SOUTH INDIAN POPULATION

Objective: Foramen magnum is an oval opening present in the median region of the posterior cranial fossa of the occipital bone. The lower end of the medulla, meninges, spinal arteries, and spinal roots of accessory nerve pass through the foramen. Morphometry of the foramen magnum is studied for better learning of the structure, but this study helps in planning a safe surgery and exploration in the head-and-neck region. Various surgical approaches of the foramen provide access to the foramina on the base of the skull and prevent broad retraction of the neurovascular structures passing through them, so the morphometric study plays an important role in transcondylar approach. Methods: Fifty dry human skulls available in the Department of Anatomy, Amala Medical College and Hospital, and also at Jubilee Medical College and Hospital, Thrissur were studied for this research work, and results were statistically analyzed. Results: The most common shape of the foramen magnum was oval, the mean of anteroposterior diameter was greater than the mean of transverse diameter, p-value of the diameters was found to be significant, p-value of the mean of foramen magnum index was significant. Conclusion: This study will help the surgeons to effectively plan a surgery at the head and neck site